Shrine of St. Magnus, Catholic pilgrimage church in Castelmagno, Italy

The Sanctuary of San Magno is a pilgrimage church in the Grana Valley, in the municipality of Castelmagno, at 1761 m a.s.l. along the road to Colle Fauniera. Rebuilt in the 18th century to a design by Giuseppe Galletto, it measures over 25 m in length, 15 m in height and 15 m in width, with two side altars and side porticoes added in 1861-68 with pilgrim lodgings above.

Don Enrico Allemandi founded the first chapel in 1475 to mark twenty-five years as parish priest of Castelmagno. A larger church replaced it in 1514, decorated by the Franciscan Giovanni Botoneri. In 1527 Pope Clement VII granted an indulgence, and the present building was completed in 1716 to a design by Giuseppe Galletto of Lugano. The bell tower was raised in 1845-48 and the side porticoes with pilgrims' lodgings added in 1861-68.

The sanctuary's feast is held on 19 August, when pilgrims bring animals to invoke Saint Magnus, protector of livestock and pastures. The fifteenth-century Allemandi chapel behind the main altar was decorated in 1514 by the Franciscan Giovanni Botoneri with frescoes meant to teach the Gospels to a poor, illiterate population; saints tied to local tradition appear alongside the Passion.

The sanctuary stands at 1761 m on the road climbing to Colle Fauniera, in the municipality of Castelmagno. It is normally open and staffed from June to September, when lodging and meals are offered to pilgrims in the adjoining quarters. Outside that season the site is not regularly accessible.

A Roman altar to Mars, found in 1894 during floor work in the old chapel, is set into the rear wall of the shrine; it points to pagan worship on the site before Christianization. The same excavation uncovered burials and other finds, many lost through careless digging.